Production of Activated Carbon from Waste Palm Oil Shells and Its Adsorption Characteristics on Copper (II)

The alarming problems of high concentration industrial effluents in the wastewater
had awakened the world to the development of the techniques for the removal of
these effluents from wastewater. Present of heavy metal such as copper in
wastewater especially from plating and semiconductor industries can directly
influence human health by impairing mental and neurological functions of the body
system. Adsorption has demonstrated efficiency and economic feasibility as a
wastewater treatment operation by using activated carbon due to its well-developed
porous structure and tremendous surface area. The production of activated carbon
from waste palm oil shell via chemical activation and carbonization were done.
Various parameters that might affect the adsorption capacities of copper (II) in
wastewater for the produced activated carbon were studied. These parameters
included the activation agent (H2S04, ZnCl2, CaCl2 and NaOH), carbonization time
(1 hr and 3 hrs), carbonization temperature (400°C and 500"C), particle sizes of the
raw material (<lmm, l-2mm and >2mm) and the preparation sequences (sequences
of carbonization and activation). In addition to that, the effects of different
wastewater conditions included the pH of the wastewater solution and the metal
concentrations in the wastewater were investigated. The results showed that the best
activation agent for production of high quality adsorbent was NaOH and then
followed by the sequence H2SO4 > ZnCl2 > CaCl2 whereas the best adsorption
capacity of copper ion from wastewater was the activated carbon produced from
particle size < 1mm and then followed by particle size 1 - 2 mm and > 2mm. The
maximum adsorption capacity for the activated carbon produced from NaOH
activation at particle size < 1mm was the highest among others, 196.06mg/g. The
activated carbon produced at 3 hr had shown a higher adsorption capacity then
produced at 1 hr. Besides, the higher the carbonization temperature, the better the
adsorption capacity will be for that activated carbon. The results also showed that
activated carbon prepared by carbonization first and then activation had a better
adsorption capacity. From the adsorption study, it can be concluded that the best
conditions of industrial wastewater for removal of copper ions were at pH 10 and
lOppm. The adsorption data for the carbons produced obeyed Langmuir Isotherm at
which the maximum adsorption capacity was 126.58 mg/g for activated carbon
activated by H2S04 at < 1mm and 93.46 mg/g for the particle size l-2mm.